First off I just wanna say thank you for interceding and helping out the poor little bufo. Second, it's a big no-no of mixing species, species toxins and aggressive behavior can/will cause the death of animals involved. IMO, I would keep the toad over the hot season and release it when the weather breaks, and release it in a wildlife preserve. OR you can just give Todd time to settle in and enjoy your new found friend. As for returning back into the wild, as long as he can hunt and burrow no problem. Just keep in mind you that you are committing to several years of being a caregiver to this little one. Toads are my fav and I've keep several. Mainly just raise little ones and release them back into the wild. Except for my Morph, he IS the ruler over his kingdom, plus he doesn't hibernate for more than 45 days so he's not able to go back into the wild. Which is fine with me.
Before you consider getting another frog/toad please do your research first Frog Forum - Care Articles this might help.